Dental casting-machine



.I. H. FRENCH. DENTAL CASTING MACHINE. APPLICATION FILED FEB. 2 4, I921- Patented Dec. 13, 1921.

- 1,400,044. I T H INVENTOR'.

J.H .French. WW

J.- H. FRENCH. DENTAL CASTING MACHINEQ APPLICATION FILED FEB 24,192!

Patented 1m.- 13, 1921-.

2 sums-surf 2- name STATES PAT ear QFFECQE JOSEPH rmnnrson rnir vcrr, or rnTERBono; oivrimro, CANADA.

Dnn'rAL CASTING-MACHINE.

T 0 all whom it may concern:

Be it known that I, Josnrrr HARRISON Finance, of the city of Peterboro, in the county of .Peterboro, inthe Province of Ontario, Canada have invented certain new and useful Improvements in Dental Casting- Machines, of which the following is the specification. c

My invention relates to improvements in dental casting machines and the object of the invention is to devise a simple, cheap and. effective apparatus for casting dental fillings which will always'be set up ready for use. A further object is to construct an apparatus in which the sealing member for the will press down uniformly- A still further object is to demold casing on the same. vise a dental casting machine which will cast from the smallest inlay casting to a plate. Another object is to devise a simple and effective control air valve'for the apparatus and another object is to provide means whereby mold casings of difierent diameters may be conveniently held in place in the apparatus. Another object is to construct a machine in which the entire working mechanism will be carried on a swingable bracket which is limited to a definite forward and backward movement.

My invention consists of a dental casting machine constructed and arranged all as hereinafter more particularly described and illustrated in the accompanying drawing in with the lugs 2.

which t Figure 1 represents a side elevation of my machine.

Fig. 2 is a vertical section through the con-,

trol valve showing the same in the closed position.

Fig. 3 is a similar view to Fig.2 but reversed thereto, and s Fig. i is a plan view of the base of the apparatus showing the means for holding mold casings of difierent diameters in place.

Fig. 5 is a vertical section showing the device applied to a mold casing and inlay mold.

Like characters of reference indicate corresponding parts in the different views:

1 is the base plate of the machine provided Screws may be passed through the lugs 2 to hold the machine firmly on a suitable supporting-structure. 3 are suitably spaced lugs extending upwardly from the base plate 1 in the vicinity of one end thereof 1: is a swingah e bracket-suit- Specification of Letters Patent. Pateflfed 13;, 19 21; Application filed February 124; 1921. Serial IiToL4 47i579. V

ably pivoted at its lower end by the pinofi betweenthe lugs 3, said bracket'being pro v ded wlth a foot 6 carrying a screw 7 provided with the lock nut 8, the lowerend of thescrew 7 being adapted-to engagethe up per face ofthe base plate 1. 9 isa hollow boss formed on the bracket 1 and constitutg the ng for the plunger 10 which i slldable therein. I

11 is an armextending upwardly from arm. 15 is the air valve casing suitably secured t'o the lower end of the plunger 10 and The lower end of the plunger 10 has a central aperture extending up thereto a cerstem 1?, said valve stembeing provided with havinga laterally extending hollow boss 16.

'tain extent and adapted to receivethe valve I a flattened face 18 and anopposed slot 19 adapted to receive the inner end of the setscrew 20. 21 1s a cross orifice extending into the interior of the stem from the" flattened surface thereof and communicating with a I vertical orifice 22 extending to the bottom of the stem. 23 and 2 1 are plates suitably secured to the valve stem 17, and 25 is a' gasket of resilient material below said plates also secured to the stem l7by the flat nut 26.

27 are-clips adapted to hold the outer peas will hereinafter appear.

'28 is a tubular valve member ofresilient,

material provided with a suitable split cover 29, said valve member being situated in the.

riphery of the gasket 25to the plates2i; in

order that'the 'gasket25 will seal. pr0perly,.

Cler having'the upwardly extending stem 3 1.-

provided at its upper end with the weight 35. I

36 is a plate preferably formed integrally 'with the base plate '1 upon whichthe mold casing 37 is adapted torest. 38 are studs adapted to' center-(the largest mold casing 4E1. 1O are removable studs adapted to center the mold casing 37', said studs being capable of being removed and inserted into-the'holes l2and thus center the smaller mold casing l3. 7 i5 is a spring interposed between the top r of the central aperture 44 above referred to and normally holdin the valve stem in the. position shown in *ig. 2 with the valve closed.

48 is an inlay mold of plaster of Paris or other suitable material and provided at its upper end'with a concavity 49 from which extends achannel 50 leading to the cavity 51 which corresponds in shape to the dental casting. 4

The machine is used as follows: The molten gold or other metal is poured into the mold 48 within the casing 43 and to 'setscrew is provided for preventing the turning of the valve stem relatlvelyto the facilitate this operation the bracket 4 is swung back about the pin 5 until the pin 46 comes into engagement with the top of the lug 3. Thus when the bracket is swung back the mold and the gold is perfectly visible so that the metal during the process of heating can be closely observed until the proper fluidity for casting is obtained, the operator being able to stand in the normal upright position.

It is to be understood that the metal is preferably preheated to just below fluid state on a block of charcoal or crucible with an oxyacetylene or oxy-hydrogen torch. The

metal is then transferred to the mold 49 by pincers or other suitablemeans. The heat is then continued by said torch until the proper fluid state is reached.

The weight 35 and the attached piston rod and piston 33 is then pulled up the required extent in the air compression cylinder 32. In

this position the air valve will be closed.

The handle of the lever 12 is now grasped by the operator and the bracket 4 is swung over until the plunger 10, the plates 23 and 24 and the attached gasket 25 are immediately above the mold casing 43, which is centered by the respective pins depending on the size of mold casing used. I

The lever 12 is now pressed downwardly I which causes the plunger 10 and the attached valve casing and gasket 25 to be pressed down until the gasket comes into engagement with the lip of the mold casing 43, thus forming an effective seal.

By pressing the lever'12 down a further extent it will be seen that as the valve stem 17 attached to the plates23 and 24 and gasket 25 will not be permitted to move down a further extent, thereforethe valve casing 15 .will be moved down by the plunger 10 relatively to the valve stem, thus compressing the spring 45 in the aperture 44. When the lever 12 is down the full extent the longitudinal orifice 47 in the valve member 28 will register with the cross aperture 21 in the valve stem. Consequently air will be forced from the air compression cylinder 32, through the hose 31, through the nipple 30, orifice 47 in the resilient valve member, through the horizontal orifice 21 and vertical orifice 22 in thevalve stem and finally force the metal down through the channel 50 into valve casing 15 and the plunger 10, but'owing to such'setscrew being inserted into the vertical slot 19 the valve stem is permitted the vertical movement referred to above. 1

From the abovedescription it will be seen that I have devised a simple and effective dental casting machine in which the pressure on the gasket 25 will be vertical and consequently the pressure on the upper lip of the mold casing 43 will be uniform.

In addition I have devised a simple and effective air valve therefor which will be positive in action and which can be readily adjusted due to Wear.

What I claim as my invention is.

1. In a dental casting machine, the combination'with the base plate and ahinged bracket thereon, of a mold detachably mounted on the said base plate, amold cover,a vertical plunger slidably mounted on the hinged bracket, said vertical plunger having an orifice extending 'up from the bottom thereof, a valve casing mounted'on the lower end of the said plunger, a valve stem secured at its lower end to the mold cover and extending up through the valve casing into the orifice in the plunger, said valve stem having a vertical orifice extending up therethrough for a certain extent and communicating with a horizontal orifice opening in the side of the stem, a spring interposed between the top of the valve stem and the top of the orifice in the plunger, means for preventing the rotation of the valve stem relatively to the plunger and valve casing, a valve member adapted to engage the valve. stem, and means for admitting air through the valve member and through the valve stem, and through the mold cover into the mold upon the horizontal orifice in the valve stem registering with the corresponding orifice in the tom thereof, a valve :casingmounted on the lower end of the said plunger, a valve stem stem having a vertical orifice'extending up therethrough for: a certain extent and communicating with a horizontalzorifice opening in the side of the stem, a spring interposed between the top of the valve stem and the top of the orifice in the plunger, means for preventing the rotation of the valve stem relatively to the plunger-and valve casing, a valve memberada-pted to engagethe valve stem, a vertical air cylinder, a weighted piston fittingthe cylinder and, adaptedto create air pressure therein, a hose connecting the bottom of the cylinder with the valve casing for admitting air under pressure through the valve member into the valve 1 stem and through the mold cover into the mold upon the horizontal orifice in the valve stem registering with the corresponding orifice in the valvemember 3. In a dental casting machine, thecombination' with the base plate and a hinged bracket thereon, of a mold detachably mounted on the said base plate, a mold cover, a vertical plunger slidably mounted.

on the hinged bracket, said vertical plunger having an orifice extending up from the bottom thereof, a valve casing mounted on the lower end of the said plunger, a valve stem secured at its lower end to the mold cover and extending up through the valve casing into the orifice in the plunger, said valve stem having a vertical orifice extending up therethrough for a certain extent and communicating with a horizontal orifice opening in the side of the stem, a spring interposed between the top of the valve stem and the top of'the orifice in the plunger, means for preventing the rotation of the valve stem relatively to the plunger and valve casing, a valve member adapted to engage the valve stem, a vertical air cylinder, a weighted piston fitting the cylinder and adapted to create air pressure therein, a hose connecting the bottom of the cylinder with the valve casing for admitting air'under pressure throughthe valve member into the valve stem and through the mold cover into the mold upon the horizontal orifice in the valve stem registering with the corresponding orifice in the valve member and means for moving the vertical plunger in a downward direction.

' d. In a dental casting machine, the combination with the base plate and a hinged bracket thereon, of a mold detachably mounted on the said base plate, a mold cover, a vertical plunger slidably mounted on the hinged bracket, said verticalplunger having an orifice extending up from the bottom thereof, a valve casing mounted on the lower end-ofthe said plunger, a valve stem-secured v at its lower end to the mold cover andextending up-through the valve casing-into the orifice in the plunger, said valve stem' having a vertical orifice extending-911p therethrough for a certain extent and communieating with a horizontal orifice opening ,in theside of the stem, aspring mterposed-be- 1 tween the top of the valve-stem and the top of-the orifice in theplunger, means for preventing the rotation of the valve stem rel atively' to the plunger and valveicasingya valve member adaptedito engage the valve I I sa e vertical air cylinder, a weighted pis-' ton-fitting the cylinder andadapted to create airpressure therein, a ;hose=connecting the bottom ofthe cylinder with the-valve casing for admitting air under pressure through the valve member into the valve stem and through the mold cover into the mold upon the horizontal orifice in the valve stem registering with the corresponding orifice in the valve member, said hinged bracket having an upwardly extending arm, a lever fulcrumed on said arm and pivotally connected intermediately of its length to the upper end of the vertical plunger. i I

5. In a dental casting machine, the combination with the base plate and bracket hinged thereto, of a vertical plunger slidably mounted on the bracket, said vertical plunger having an orifice extending up a certain extent from its lower end, a mold cover, a resilient gasket on the lower face of the mold cover, a valve stem secured to the mold cover and adapted to extend up through the valve easing into the orifice in the plunger, a spring interposed between the top of the valve stem and the top of they orifice, said valve stem having a vertical orifice extending up from its lower end and communicating with a horizontal orifice and communicating with the outside of the valve stem, a setscrew extending through the valve casing adapted to engage a vertical slot in the valve stem, one side of the valve stem being flattened, a resilient valve member having a central orifice extending therethrough, the

the valve stem, a nipple adapted to engage the outer end of the valve member and capable of being adjusted to hold the valve member in engagement with the valve stem.'

6. In a dental casting machine, the combination with the base plate and bracket hinged thereto, of a vertical plunger slidably mounted on the bracket, said vertical plunger havingan orifice extending up a certain extent frem its lower end, a mold cover, a resilient gasket on the lower face of the mold cover, a valve stem secured to the mold cover and adapted to extend up throughlthe valve casing into the orifice in the plunger, a spring interposed between the top of the valve stem and the top of the orifice, said valve stem having a vertical orifice extending up from its lower end and communicating with a horizontal orifice and communieating with the outside of the valve stem, a setscrew extending through the valve casing adapted'to engage a vertical slot in the valve stem, one side of the valve stem being flattened, a resilient valve member having a central orifice extending ther'ethrough, the

vinner end of the resilient valve member adapted-to engage the flattened surface of the valve stem, a nipple adapted to engage the outer end of the valve member and capable of being adjusted to hold the Valve member in engagement with the valve stem,

a foot on the hinged bracket, a setsorew extending through said foot and provided with a lock nut, the lower end of the screw engaging the base plate for limiting the'in ward movement of the hinged bracket and a pin on the side of the bracket for limiting its outward movement.

7. In a dental casting machine, the combi nation with the different sized circular molds and a base plate having a plurality of suitably spaced concentric holes in the upper surface thereof, said holes being situated'in different radii corresponding with the radii of the different molds, of a plurality of pins inserted into any selected set of holes for holding the corresponding mold in its centered position. I V

JOSEPH HARRISON FRENCH. 

